JP2848354B2 - Magnetic head slider and magnetic disk drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head slider and a magnetic disk drive, and more particularly, to a contact type magnetic disk drive in which a magnetic head slider moves closely in contact with a magnetic disk medium to perform recording and reproduction.

[0002]

2. Description of the Related Art In recent years, in the field of information storage files, recording density has been steadily improved. For this reason, in the magnetic disk device, making the gap between the magnetic head for writing / reading information and the magnetic disk medium holding the information smaller is one of the important factors for high-density recording. I have. In order to reduce the gap between the magnetic head and the magnetic disk medium, a so-called contact magnetic disk device that performs recording and reproduction while the magnetic head slides on the surface of the magnetic disk medium has been developed (for example, "H"). Hamilton: Journal of
Magnetic Society of Japan
n, Vol. 15, Supplement No. 15; S
2 (1991) 483 "and" Japanese Patent Application No. 5-5088.
08 (Tokuhyohei 5-814495) ").

In this type of contact type magnetic disk drive, a lubricant is applied onto the magnetic disk medium in order to prevent wear and tear of the magnetic disk medium and the contact pads of the magnetic head slider due to contact between them.

However, in such a contact type magnetic disk drive, the lubricant on the magnetic disk medium moves to the outer peripheral part by the centrifugal force caused by the high-speed rotation of the magnetic disk medium, so that the inner peripheral part and the middle part of the magnetic disk medium are moved. In the peripheral portion, a phenomenon occurs in which the thickness of the lubricant decreases.

[0005] In a floating magnetic disk drive, a CSS (Contact Start Stop) is also used.
When the method is adopted, the magnetic head slider and the magnetic disk medium are not moved until the magnetic head slider flies above the magnetic disk medium at the start of operation and until the rotation of the magnetic disk medium stops at the time of stop. Are in a sliding state. Therefore, in such a magnetic disk device, the lubricant is applied on the magnetic disk medium, and there is a problem regarding the depletion of the lubricant.

As a technique for preventing the depletion of the lubricant on the magnetic disk medium with respect to such a conventional levitation type magnetic disk apparatus, the following techniques have been proposed. In addition, the bonding between the lubricant and the protective film has been strengthened by making the lubricant applied thereon to have a polar group (see "JP-A-6-333231").

Further, as a technique for preventing the depletion of the lubricant on the magnetic disk medium with respect to the conventional contact magnetic disk apparatus, a lubricant is applied to the surface of the magnetic disk medium by a capillary phenomenon in a head suspension. The head suspension wick integrated system to be supplied has been applied ("JP-A-6-223533").
reference).

[0008] As another technique of "a technique for preventing the lubricant on the magnetic disk medium from being depleted", as the leading edge of the contact pad is made wider than its trailing edge, the contact pad is provided under the contact pad. The lubricant on the magnetic disk medium is prevented from decreasing (see JP-A-6-12808 and JP-A-6-44718).
In addition, even when a skew angle occurs when the magnetic head moves from the inner circumference to the outer circumference of the magnetic disk medium, the shape of the contact pad is optimized in order to suppress a decrease in lubricant under the contact pad. Is described in Japanese Patent Application Laid-Open No. 7-147.
No. 070 gazette ". By making the angle of the side of the contact pad larger than the maximum absolute value of the skew angle, when the magnetic head slider moves from the inner diameter to the outer diameter of the magnetic disk medium, lubricant is reduced over the entire angle range of the seek operation of the contact pad. It has a deterrent effect. Also, in the above-mentioned Japanese Patent Application Laid-Open No. 7-147070, it is described that the leading edge is not parallel to the trailing edge as the contact pad shape. The edges are intended to provide extra air bearing lift at the disk inner diameter where the local disk speed is lower, and to provide less lift at the disk outer diameter where the air bearing effect is greater due to the higher local disk speed. there were.

[0009]

In the above-mentioned conventional contact type magnetic disk drive, the lubricant on the magnetic disk medium moves to the outer periphery by the centrifugal force caused by the high-speed rotation of the magnetic disk medium. Since the thickness of the lubricant decreases at the inner and outer peripheral portions, there is a problem that the magnetic disk medium and the magnetic head slider (contact pad) are worn and damaged. Such a problem has been an obstacle to realizing high recording density and high reliability of the contact type magnetic disk device.

In order to avoid such a problem, CS
With the "technology for strengthening the connection between the lubricant and the protective film" adopted in the S-type floating magnetic disk device, the bonding force between the lubricant and the protective film on the magnetic disk medium is increased in the contact type magnetic disk. However, it has not been possible to prevent wear damage of the magnetic disk medium and the magnetic head slider. The reason is that in a contact type magnetic disk device, the magnetic head slider and the magnetic disk medium are always in contact,
This is because the lubricant on the magnetic disk medium easily moves, and the effect of increasing the bonding force between the lubricant on the magnetic disk medium and the protective film hardly occurs.

Further, it is difficult to apply a method of supplying a lubricant onto a magnetic disk medium by a wick to a thin lubricating film having a thickness of 1 μm or less, and cannot be applied to a contact type magnetic disk corresponding to a high recording density. . The reason for this is that if the lubricating film is thickened, the distance between the magnetic head and the magnetic disk medium increases, and a high recording density cannot be achieved because the recording density greatly depends on the distance between the magnetic head and the magnetic disk medium. .

Further, in the shape of the contact pad disclosed in JP-A-6-12808, JP-A-6-44718 and JP-A-7-147070, the lubricant is formed by centrifugal force. Is difficult to prevent from moving to the outer periphery. The reason is that the lubricant cannot be moved from the outer peripheral portion to the inner peripheral portion of the magnetic disk medium with these contact pad shapes.

SUMMARY OF THE INVENTION An object of the present invention is to provide a high-density and high-reliability magnetic disk device which realizes a sufficient degree of prevention of abrasion damage of a magnetic disk medium and a magnetic head slider in view of the above points. It is in. In particular, it is an object of the present invention to provide a magnetic head slider capable of moving a lubricant moved in an outer circumferential direction by a centrifugal force in an inner circumferential direction. Also,
It is another object of the present invention to provide a magnetic disk drive having the magnetic head slider.

[0014]

The operation of the present invention will be described.

FIG. 1 is a perspective view showing an example of a magnetic head slider according to the present invention. Two contact pads A each having a groove formed in front of the magnetic head slider in the traveling direction;
One contact pad B having an asymmetrical shape is arranged behind the magnetic head slider in the traveling direction. The contact pad A and the contact pad B act as a portion that receives pressure when moving relatively in close contact with the magnetic disk medium, and at the same time, apply the lubricant applied on the magnetic disk medium from the outer peripheral portion to the inner peripheral portion. It is characterized by having a function of moving.

FIG. 2A is a diagram showing a state in which a contact pad used for a magnetic head slider according to the present invention slides on a magnetic disk medium. FIG. 2 (b)
FIG. 11 is a diagram illustrating a state in which a contact pad used in a conventional magnetic head slider slides on a magnetic disk medium. In FIG. 2B, the state in which the lubricant is separated by the contact pad is symmetrical in the inner circumferential direction and the outer circumferential direction of the magnetic disk medium. It can be seen that the flow of the agent is asymmetric at the inner and outer circumferences, and that the lubricant is moving from the outer circumference to the inner circumference.

FIGS. 3A and 3B show another contact pad used in the magnetic head slider of the present invention and FIG. 3B showing a state in which the contact pad slides on the magnetic disk medium. is there. The foremost part (point A) and the innermost part (B) of the contact pad in the direction of travel of the magnetic head slider.
The magnitude of the radial component (AB ′) of the line segment (AB) connecting the points (AB) is determined by the line segment (Point A) connecting the foremost portion (point A) of the contact pad in the direction of travel of the magnetic head slider and the outermost portion (point C). A
By making the magnitude of the radial component (AC ') larger than that of C), the flow of the lubricant is asymmetrical at the inner and outer circumferences, like the contact pad A shown in FIG. The lubricant can be moved to the part.

In the present invention, the principle of operation is that the force of the magnetic head slider sliding on the magnetic disk medium is converted into the force of moving the lubricant from the outer circumference to the inner circumference by the shape of the contact pad. . As a result, it is possible to prevent the lubricant on the magnetic disk medium from being depleted even in the inner peripheral portion and the middle peripheral portion.

Further, when the magnetic head slider performs a seek operation from the outer peripheral portion to the inner peripheral portion of the magnetic disk medium at predetermined time intervals, or when the magnetic disk device does not perform the seek operation for a predetermined time, By performing the seek operation of the magnetic head slider from the outer peripheral portion to the inner peripheral portion of the magnetic disk medium, the effect of preventing the depletion of the lubricant becomes remarkable. The reason is that if the seek operation interval is too long or if the seek operation is not performed over the entire surface of the magnetic disk medium, the lubricant cannot be resupplied to the entire surface of the magnetic disk medium.

The mass of the magnetic head slider is 0.1
Even when the amount is from 10 mg to 10 mg, the effect of preventing the depletion of the lubricant becomes remarkable. The reason is that if the mass of the magnetic head slider is too small, the sliding becomes unstable due to the resistance when the contact pad pushes the lubricant, and the lubricant cannot be supplied, and the mass of the magnetic head slider is too large. This is because it is impossible to follow the magnetic disk medium and supply of the lubricant becomes impossible.

According to the present invention, it is possible to prevent wear and damage of the magnetic head slider and the magnetic disk medium based on the above principle, and to realize a high recording density and a high reliability of the magnetic disk device.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, specific embodiments of the contact type magnetic disk drive of the present invention will be described.

FIG. 4 is a sectional view showing the basic structure of the contact type magnetic disk drive of the present invention.

The substrate 45 has a diameter of 90 mm and a thickness of 0.3 mm.
3 mm glass is used.

The underlayer 46 is made of Cr by sputtering.
Is formed to a thickness of 100 nm.

The magnetic material 47 is made of CoC by sputtering.
rTaPt is formed to a thickness of 30 nm.

The protective film 48 is formed by depositing diamond-like carbon to a thickness of 5 nm by sputtering.

The lubricant 49 is formed by dipping a perfluoropolyether to a thickness of 10 nm in principle. In addition, as described later, the thickness of the lubricant 49 is changed. In this case, the change in the film thickness of the lubricant 49 is realized by controlling the concentration of the dip solution.

The suspension spring 41 has a length of 10 mm,
Stainless steel having a width of 0.5 mm and a thickness of 0.03 mm is used. The load when pressing the magnetic head slider against the magnetic disk medium by the suspension spring is 500
mgf.

The spring support mechanism 42 has a length of 15 mm and a width of 3 mm
And a stainless steel having a thickness of 1 mm is used.

The seek mechanism 43 uses a voice coil motor.

The magnetic head slider 10 is essentially the width 1mm, the length 1.2mm and a thickness of 0.3mm Al ₂ O ₃ -
TiC is used and its mass is 2 mg. Further, when changing the mass of the magnetic head slider, the dimensions or the material of the magnetic head slider were changed.

As the magnetic recording / reproducing element 40, a thin film head using a NiFe alloy thin film as a yoke material is used.

The contact pad A11 is made of Al ₂ O ₃ −
After depositing 4 μm of diamond-like carbon on a TiC substrate by a chemical vapor deposition method,
One formed by milling with argon ions was used. The pattern shape of the contact pad surface is
As will be described later, it was changed by changing the mask shape and the milling conditions.

FIG. 1 is a perspective view of a magnetic head slider according to an embodiment of the present invention. In the magnetic head slider shown in FIG. 1, two circular contact pads A each having a groove formed in the front in the traveling direction of the magnetic head slider, and one contact pad B having the shape shown in FIG. These two contact pads were respectively arranged at the following positions.
The contact pad A had a diameter of 30 μm centered on a position 50 μm from the front edge in the traveling direction of the magnetic head slider and 50 μm from the inner and outer peripheral edges. The contact pad B was arranged at the center of the inner and outer circumferences of 50 μm from the rear edge in the direction of travel of the magnetic head slider. In addition,
The groove depth of the contact pad is 10 nm, the groove width is 5 μm,
The angle between the longitudinal direction of the groove and the direction of movement of the slider was 30 degrees. The dimensions of the contact pad shown in FIG. 3 are as follows: AC ′ = 10 μm, AB ′ = 20 μm, B′D = 3
0 μm and C′E = 30 μm.

FIG. 5 shows an example of a slider in which a groove is formed in the inner / outer asymmetric contact pad. By combining the groove formation and the inner / outer periphery asymmetry, the effect is expected to be more remarkable than when each is used alone. The shape of this contact pad is AC ′ = 1 in FIG.
0 μm, AB ′ = 20 μm, B′D = 30 μm, C′E
= 30 μm, the groove depth is 50 nm, the groove width is 7 μm, the angle between the longitudinal direction of the groove and the slider traveling direction is 45 degrees, and the position of the groove is set so that the center of the groove passes through the center of gravity of the contact pad. Placed.

These magnetic head sliders are attached to a suspension spring 41 as shown in FIG. 4, and this suspension spring is attached to a seek mechanism 43 via a spring support mechanism 42. Magnetic head slider 10
Is a magnetic disk medium 44 rotating at 5400 rpm.
, And is moved in the radial direction of the magnetic disk medium by the seek mechanism 43.

The substrate 45, the underlayer 46, the magnetic material 4
7, protective film 48, lubricant 49, magnetic head slider 1
0, magnetic recording / reproducing element 40, suspension spring 41,
The material and forming method of the spring support mechanism 42, the seek mechanism 43, and the contact pad A11 are not particularly limited, and known materials and forming methods can be used without any particular limitation.

[0039]

【Example】

[Examples 1 to 7] The contact pad A shown in FIG. 2A was placed 50 μm from the front edge in the traveling direction of the magnetic head slider, and 50 μm from the inner and outer edges, respectively.
And two at the center of the inner and outer circumferences of 50 μm from the rear edge in the direction of travel of the magnetic head slider.
A plurality of magnetic head sliders were used. The diameter of the contact pad was 30 μm, the width of the groove was 5 μm, and the angle between the longitudinal direction of the groove and the traveling direction of the slider was 30 degrees. A 10 nm perfluoropolyether lubricant was applied to the magnetic disk medium. The groove depth of the contact pad was varied from 0.1 nm to 3000 nm as shown in Table 1.

[0040]

[Table 1]

[Embodiments 8 to 15] The contact pad B shown in FIG. 3 was placed at a position centered at a position 50 μm from the rear edge in the direction of travel of the magnetic head slider and 50 μm from each of the inner and outer peripheral edges. Two magnetic head sliders, one at the center of the inner and outer circumferences of 50 μm from the front edge in the direction of travel of the magnetic head slider, were used. The contact pad shape is B'D = 30 μm in FIG.
, C′E = 30 μm. AB 'length and A
As shown in Table 2, the length of AB ′ was 10 μm.
m or 20 μm, the length of AC ′ is 5-30.
μm. A hydrocarbon-based lubricant was applied to a thickness of 10 nm on the magnetic disk medium.

[0042]

[Table 2]

Embodiments 16 to 23 FIG. 2 (a)
The two contact pads A shown in FIG. 3 are located at a position 50 μm from the front edge in the traveling direction of the magnetic head slider and 50 μm from the inner and outer peripheral edges respectively, and 50 μm from the rear edge in the traveling direction of the magnetic head slider. One magnetic head slider was used at the center of the inner and outer circumferences. Contact pad diameter is 30μm, groove width is 5μ
m, the angle between the longitudinal direction of the groove and the slider travel direction is 4
0 degrees. The groove depth of the contact pad was 100 nm. The lubricant applied on the magnetic disk medium was a perfluoropolyether-based lubricant, and the film thickness was varied from 0.1 to 300 μm as shown in Table 3.

[0044]

[Table 3]

Embodiments 24 to 31 The contact pad B shown in FIG. 3 was placed at a position centered at 50 μm from the front edge in the direction of travel of the magnetic head slider and 50 μm from the inner and outer edges. Two magnetic head sliders were used, one at the center of the inner and outer circumferences of 50 μm from the rear edge in the direction of travel of the magnetic head slider. The contact pad shape is AC ′ = 10 μ in FIG.
m, AB ′ = 20 μm, B′D = 30 μm, C′E = 3
It was set to 0 μm. The lubricant applied on the magnetic disk medium was a perfluoropolyether-based lubricant, and the film thickness was varied from 0.1 to 300 μm as shown in Table 3.

Embodiment 32 Two contact pads D shown in FIG. 5 were placed at the center of a position 50 μm from the front edge in the direction of travel of the magnetic head slider and 50 μm from the inner and outer edges, respectively. One magnetic head slider was used at the center of the inner and outer circumferences of 50 μm from the rear edge in the head slider traveling direction. The contact pad D is AC ′ = 10 μm and AB ′ = 20 in FIG.
μm, B′D = 30 μm, C′E = 30 μm, the groove depth is 50 nm, the groove width is 7 μm, the angle between the longitudinal direction of the groove and the slider traveling direction is 45 degrees, and the center of the groove is the contact pad. The position of the groove was arranged so as to pass through the position of the center of gravity. The lubricant applied on the magnetic disk medium was a perfluoropolyether-based lubricant, and the film thickness was 10 nm.

Embodiments 33 to 42 The contact pad B shown in FIG. 3 was placed at a position centered at 80 μm from the front edge in the direction of travel of the magnetic head slider and 70 μm from the inner and outer edges. Two magnetic head sliders were used, one at the center of the inner and outer circumferences 60 μm from the rear edge in the direction of travel of the magnetic head slider. The contact pad shape is AC ′ = 12 μ in FIG.
m, AB ′ = 23 μm, B′D = 35 μm, C′E = 3
It was 5 μm. The lubricant applied on the magnetic disk medium is a perfluoropolyether-based lubricant, and the film thickness is 1
It was set to 0 nm. The mass of the magnetic head slider was changed from 0.01 to 50 mg as shown in Table 4.

[0048]

[Table 4]

[Comparative Example] In order to compare the embodiment of the present invention with the conventional art, FIG. 2 shows an example (comparative example) of a conventional magnetic head slider which does not employ the concept of the present invention.
The contact pad C shown in (b) is centered at a position 50 μm from the front edge in the traveling direction of the magnetic head slider and 50 μm from the inner and outer edges, respectively.
Pieces, 50 μm from the rear edge in the direction of travel of the magnetic head slider
One magnetic head slider was used at the center of the inner and outer circumferences. The diameter of the contact pad was 30 μm.
The thickness of the lubricant applied on the magnetic disk medium is 100
nm.

The magnetic head sliders shown in the above-described Examples 1 to 42 and the comparative example were placed on a magnetic disk medium rotating at 5400 revolutions per minute by a radius of 23 mm to 42 mm.
The entire surface of the magnetic disk medium was sought once per minute, and then slid at random radial positions to perform recording and reproduction. A sliding durability test was performed to repeat these operations. As a method for evaluating the reliability of the contact magnetic disk device, the operating time when the error rate of the recording / reproducing signal was twice the initial value was determined. Tables 1 to 4 show test results (operating time) of the sliding durability test.

Embodiments 43 to 52 The contact pad B shown in FIG. 3 was placed at a position centered at 50 μm from the front edge in the direction of travel of the magnetic head slider and 50 μm from the inner and outer edges. Two magnetic head sliders were used, one at the center of the inner and outer circumferences of 50 μm from the rear edge in the direction of travel of the magnetic head slider. The contact pad shape is AC ′ = 10 μ in FIG.
m, AB ′ = 20 μm, B′D = 30 μm, C′E = 3
It was set to 0 μm. A fluorinated carbon-based lubricant was applied to a thickness of 10 nm on the magnetic disk medium. These magnetic head sliders are placed on a magnetic disk medium at 5400 revolutions per minute with a radius of 2
The seek operation was performed once from the outer circumference to the inner circumference every three lubricant supply seek times shown in Table 5 in the range from 3 mm to 42 mm, and then sliding was performed at random radial positions to perform recording and reproduction. A sliding durability test was performed to repeat these operations. As a method for evaluating the reliability of the contact magnetic disk device, the operating time when the error rate of the recording / reproducing signal was twice the initial value was determined. Table 5 shows the test results (operating time) of the sliding durability test.

[0052]

[Table 5]

[Embodiments 53 to 62] The contact pad B shown in FIG. 3 was placed at a position centered at 50 μm from the front edge in the direction of travel of the magnetic head slider and 50 μm from the inner and outer edges. Two magnetic head sliders were used, one at the center of the inner and outer circumferences of 50 μm from the rear edge in the direction of travel of the magnetic head slider. The contact pad shape is AC ′ = 10 μ in FIG.
m, AB ′ = 20 μm, B′D = 30 μm, C′E = 3
It was set to 0 μm. A 10 nm silicone oil-based lubricant was applied on the magnetic disk medium. These magnetic head sliders are placed on a magnetic disk medium at 5400 revolutions per minute with a radius of 2
The seek operation is performed at a random time interval in a range of 3 mm to 42 mm. When the time of the non-seek operation exceeds the lubricant supply reference time shown in Table 6, one seek operation is performed from the outer periphery to the inner periphery.
A repetitive seek operation was performed, and then sliding was performed at random radial positions to perform recording and reproduction. A sliding durability test was performed to repeat these operations. As a method for evaluating the reliability of the contact magnetic disk device, the operating time when the error rate of the recording / reproducing signal was twice the initial value was determined. Table 6 shows the test results (operating time) of the sliding durability test.

[0054]

[Table 6]

Referring to the test results of Examples 1 to 62 in Tables 1 to 6 and the test results of Comparative Examples,
The following considerations are possible.

Referring to the test results of the first to seventh embodiments and the comparative example, when the traveling direction of the magnetic head slider is set to the front, the sliding surface of the contact pad is moved from the front outer peripheral portion to the rear inner peripheral portion. In the case where the groove toward the groove is formed, the operating time in which the error rate is twice the initial value is at least four times or more as compared with the case where the groove is not formed (in the case of the comparative example). That is, by providing a groove extending from the front outer peripheral portion to the rear inner peripheral portion when the traveling direction of the magnetic head slider is set to the front in the sliding surface of the contact pad, a magnetic disk device with high recording density and high reliability is provided. The effect of being able to provide can be obtained.

When the depth of the groove is 1 nm or more and 1000 nm or less, the operating time in which the error rate is twice the initial value increases. That is, by setting the depth of the groove structure to 1 nm or more and 1000 nm or less, the performance of the magnetic disk device can be more effectively improved.

Comparing the eighth embodiment to the fifteenth embodiment, when the AB ′ length in FIG. 3 is longer than the AC ′ length, the operating time at which the error rate is twice the initial value is 37 times. That's all. In other words, as the shape of the contact pad, the magnitude of the radial component of the line connecting the foremost portion and the innermost portion of the contact pad in the direction of travel of the magnetic head slider is determined by comparing the size of the contact pad with the foremost portion of the contact pad in the direction of travel of the magnetic head slider. The effect of providing a magnetic disk device with high recording density and high reliability can also be obtained by making it larger than the size of the radial component of the line connecting the outer peripheral portions.

Comparing the sixteenth embodiment to the thirty-first embodiment, when the lubricant film thickness is 1 nm or more and 100 nm or less, the operating time when the error rate is twice the initial value is 5 times.
More than doubled. That is, it is understood that the lubricant film thickness is more preferably from 1 nm to 100 nm.

The thirty-second, fifth and ninth embodiments
Comparing the working examples, the working time in which the error rate of the working example 32 is twice the initial value is the working time of the working example 5 and the working example 9
It is significantly longer than that of. In other words, as the shape of the contact pad, the magnitude of the radial component of the line connecting the foremost portion and the innermost portion of the contact pad in the direction of travel of the magnetic head slider is determined by comparing the size of the contact pad with the foremost portion of the contact pad in the direction of travel of the magnetic head slider. A groove extending from the front outer peripheral portion to the rear inner peripheral portion when the traveling direction of the magnetic head slider is set to be forward, the groove being larger than the size of the radial component of the line connecting the outer peripheral portion and the sliding surface of the contact pad. By providing the structure, the effect that “a magnetic disk device with high recording density and high reliability can be provided” becomes even more remarkable.

When comparing the 33rd embodiment to the 42nd embodiment, the mass of the magnetic head slider was 0.1 mg or more and 10 mg or less.
When the amount is less than or equal to mg, the operating time when the error rate is twice the initial value is at least four times or more as compared with the other cases. That is, it is understood that the mass of the magnetic head slider is more preferably 0.1 mg or more and 10 mg or less.

Comparing the 43rd embodiment to the 52nd embodiment, when the lubricant supply seek time is set to 1 minute or more and 1 hour or less, the error rate becomes twice the initial value as compared with other cases. The operating time has been at least doubled. In other words, it is understood that the lubricant supply seek time is more preferably from 1 minute to 1 hour.

When comparing the 53rd embodiment to the 62nd embodiment, when the lubricant supply reference time is set to 1 minute or more and 1 hour or less, the error rate becomes twice the initial value as compared with other cases. The operating time has been at least doubled. In other words, it is understood that the lubricant supply reference time is more preferably in the range of 1 minute to 1 hour.

From the above considerations, it can be seen that the magnetic disk device of the present invention achieves at least four times the durability as compared with the conventional magnetic disk device, and can ensure high reliability. .

From the above considerations, the following ranges are appropriate for “contact pad groove depth” and “lubricant film thickness” in the contact type magnetic disk drive of the present invention. It turns out that it is a suitable value.

"Groove depth of contact pad": 1 nm or more and 1000 nm or less "Lubricant film thickness": 1 nm or more and 100 nm or less The theoretical basis for the existence of a certain appropriate value range as described above is as follows. It is thought that there is.

Regarding the “depth of the groove of the contact pad”, if it is too small, such as less than 1 nm, the present invention is not applied. If it is more than 1000 nm, pressure due to air flow acts on the groove, and the lubricant Is prevented from flowing through the groove, whereby the effect of the present invention is not exhibited.

Regarding the “lubricant film thickness”, if the lubricant is too small, the lubricant is strongly adsorbed on the medium surface of the magnetic disk medium, making it difficult for the lubricant to move from the outer periphery to the inner periphery, so that the effect of the present invention is not exhibited. If it is too large, the recording / reproducing characteristics of the magnetic head deteriorate.

[0069]

As described above, according to the present invention,
The following effects are produced.

The lubricant which moves to the outer peripheral portion of the magnetic disk medium due to the centrifugal force moves from the front outer peripheral portion to the rear inner peripheral portion when the traveling direction of the magnetic head slider is set to the front on the sliding surface of the contact pad. By providing a groove, or the size of the radial component of the line connecting the foremost part and the innermost part of the contact pad in the direction of travel of the magnetic head slider, the magnitude of the radial component of the line of the contact pad with the foremost part of the contact pad in the direction of travel of the magnetic head slider can be reduced. By making the size of the radial component larger than the radius of the line connecting the outer peripheral portions, it is possible to prevent or control the decrease or depletion of the lubricant film thickness in the inner peripheral portion and the middle peripheral portion of the magnetic disk medium. Thus, abrasion damage of the magnetic head slider and the magnetic disk medium can be prevented, and a magnetic disk device with high recording density and high reliability can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a basic configuration of a magnetic head slider of the present invention.

FIG. 2 is a diagram for explaining the principle and operation of the magnetic head slider of the present invention, and shows a state in which a lubricant flows around a contact pad.

FIG. 3 is a view for explaining the principle and operation of the magnetic head slider of the present invention, and shows a state in which lubricant flows through another contact pad.

FIG. 4 is a sectional view showing a basic configuration of a magnetic disk drive of the present invention.

FIG. 5 is a diagram showing a structure of a contact pad used for the magnetic head slider of the present invention.

[Explanation of symbols]

 Reference Signs List 10 magnetic head slider 11 contact pad A 12 contact pad B 21 lubricant flow 22 contact pad C 21 magnetic disk medium 40 magnetic recording / reproducing element 41 suspension spring 42 spring support mechanism 43 seek mechanism 44 magnetic disk medium 45 substrate 46 base layer 47 Magnetic material 48 Protective film 49 Lubricant 50 Contact pad D

Claims (11)

(57) [Claims] In a magnetic head slider having a magnetic head and a contact pad, a lubricant applied to the surface of a magnetic disk medium is moved from an outer peripheral portion to an inner peripheral portion of the magnetic disk medium as the magnetic head slider slides. A magnetic head slider, wherein a structure to be provided is provided on a sliding surface of the contact pad. 2. The magnetic head according to claim 1, wherein a groove extending from a front outer peripheral portion to a rear inner peripheral portion when a traveling direction of the magnetic head slider is set to be forward is provided on a sliding surface of the contact pad. Slider. 3. The magnetic head slider according to claim 2, wherein the depth of the groove provided in the contact pad is 1 nm or more and 1000 nm or less. 4. The shape of the contact pad, the magnitude of the radial component of the line connecting the forwardmost portion and the innermost portion of the contact pad in the direction of travel of the magnetic head slider, is determined by the forward most of the contact pad in the direction of travel of the magnetic head slider. 2. The magnetic head slider according to claim 1, wherein the magnitude of a radial component of a line connecting the portion and the outermost peripheral portion is larger. 5. The shape of the contact pad, the magnitude of a radial component of a line connecting the foremost portion and the innermost portion of the contact pad in the direction of travel of the magnetic head slider is determined by determining the size of the contact pad in the forefront of the direction of travel of the magnetic head slider. Larger than the size of the radial component of the line connecting the part and the outermost part,
2. The magnetic head slider according to claim 1, wherein a groove extending from the front outer peripheral portion to the rear inner peripheral portion when the traveling direction of the magnetic head slider is set to the front is provided on the sliding surface of the contact pad. 6. A magnetic head slider having a magnetic head and a contact pad, wherein a lubricant applied to a surface of a magnetic disk medium is moved from an outer peripheral portion to an inner peripheral portion of the magnetic disk medium as the magnetic head slider slides. A structure to be provided on the sliding surface of the contact pad, and the mass of the magnetic head slider is 0.1 mg or more and 10 m or more.
g or less. 7. A magnetic disk medium having a surface coated with a lubricant, a magnetic head for recording or reproducing information by being relatively moved in close contact with the magnetic disk medium, and a magnetic head and a contact pad. 7. A magnetic disk device comprising: a magnetic head slider having a magnetic head slider; and a support spring for pressing the magnetic head slider against the magnetic disk medium, wherein the magnetic head slider is the magnetic head slider according to claim 1. A magnetic disk drive characterized by the following. 8. The magnetic disk drive according to claim 7, wherein the thickness of the lubricant applied to the magnetic disk medium is 1 nm or more and 100 nm or less. 9. The magnetic disk drive according to claim 7, wherein the magnetic head slider performs a lubricant supply seek operation from the outer peripheral portion to the inner peripheral portion of the magnetic disk medium at predetermined time intervals. Magnetic disk device. 10. A magnetic disk drive according to claim 7, wherein when the non-seek operation interval reaches the lubricant supply reference time, the magnetic head slider performs a seek operation from the outer peripheral portion to the inner peripheral portion of the magnetic disk medium. A magnetic disk drive. 11. A lubricant supply seek operation interval is 1 minute or more and 1 minute.
11. The magnetic disk drive according to claim 9, wherein the time is not more than a time.